Herodotus, the Infinite

Herodotus, the Infinite is a massive teal slime that lives in a large room containing platforms, crates and spiketraps. His basic AI pattern is to chase the player around the room, inflicting damage whenever the player collides with him. After reaching a damage threshold, Herodotus will split up in to multiple parts (32 in total) each one getting smaller and smaller, while also producing an earth mage each time a part is split.

For this boss battle, it is reccommend that you pick a high DPS (damage per second) class that is able to split a part of the boss, then easily destroy the earth mage before it can damage you. The Hokage is generally a solid choice for this battle, as is high magic power characters, like the spellthief and the Archmage.

His attack patterns are relatively easy to avoid, just keep running around the room, making sure not to linger too long on the spike traps layed around the floor. The main way to defeat this boss however, is to focus on one specific "family" of the slime at a time, allowing you to easily dispose of him one by one, rather then finding yourself inundated by tens of slimes.